In Ruby, how do I find out if a string is not in an array?

Question

In Ruby, how would I return true if a string is not in an array of options?

# pseudo code
do_this if current_subdomain not_in ["www", "blog", "foo", "bar"]

...or do you know of a better way to write this?

question from:https://stackoverflow.com/questions/5684006/in-ruby-how-do-i-find-out-if-a-string-is-not-in-an-array

Answer 1

do_this unless  ["www", "blog", "foo", "bar"].include?(current_subdomain)

or

do_this if not ["www", "blog", "foo", "bar"].include?(current_subdomain)

I'm using the Array#include? method.

However using unless is a fairly big ruby idiom.